Compilare: main.cpp:21:18: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts' 21 | void dfs1(int k, auto &S) | ^~~~ main.cpp: In function 'int main()': main.cpp:61:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 61 | for(int i=0;i<sol.size();i++) | ~^~~~~~~~~~~